种子脱水是其成熟过程中的一个关键生理过程, 直接影响种子休眠程度以及收获后种子的含水量、储存能力和品质。在农业生产中, 籽粒脱水速率是决定种子收获时籽粒含水量的主要因素之一, 也是决定机械化收获质量的关键。近年的研究表明, 种子脱水过程中转录组和激素水平发生了明显变化, 但相关分子机制研究进展非常缓慢。近期的一项研究发现了1个位于非编码区调控玉米(Zea mays)种子成熟期脱水速率的数量性状遗传位点(QTL) qKDR1, 通过招募转录因子ZmMYBST1和ZmMYBR43抑制qKDR1上游微肽编码基因RPG的转录, 导致RPG的表达量降低。研究揭示了RPG编码的微肽microRPG1通过调控乙烯信号途径影响种子脱水速率的分子机制, 并阐明了其在作物育种和农业生产中的应用潜力。该研究拓展了人们对种子脱水调控机制的理解, 为开发脱水速率更快和耐储性更强的作物品种提供了重要理论依据。

Seed desiccation is a key physiological process during plant seed maturation, directly affecting seed moisture content, storage, and quality. In agricultural practice, the kernel dehydration rate (KDR) is a critical determinant of seed water content at harvest and seed quality for mechanical harvesting. Over the past decades, although physiological changes in transcriptome and hormone levels have been linked to seed dehydration, little progress for underlying mechanisms has been achieved. A recent study identified a QTL located in a non-coding region, named qKDR1, which regulates the dehydration rate during maize seed maturation. By recruiting the transcription factors ZmMYBST1 and ZmMYBR43, it suppresses the transcription of the micropeptide-encoding gene RPG upstream of qKDR1, leading to reduced expression of RPG. The encoded micropeptide, microRPG1, regulates the KDR through the ethylene signaling pathway, highlighting its potential in crop breeding and agricultural practices. This study advances our understanding of the molecular mechanisms underlying seed desiccation and provides theoretical support for breeding crops with faster KDR and improved storage qualities.